From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751952AbcFVOQc (ORCPT ); Wed, 22 Jun 2016 10:16:32 -0400 Received: from foss.arm.com ([217.140.101.70]:48118 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751505AbcFVOQ3 (ORCPT ); Wed, 22 Jun 2016 10:16:29 -0400 Date: Wed, 22 Jun 2016 15:17:00 +0100 From: Lorenzo Pieralisi To: Sudeep Holla Cc: "Rafael J . Wysocki" , linux-acpi@vger.kernel.org, Vikas Sajjan , Sunil , Prashanth Prakash , Al Stone , Ashwin Chaugule , linux-kernel@vger.kernel.org, Mark Rutland , Daniel Lezcano , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v6 4/5] arm64: add support for ACPI Low Power Idle(LPI) Message-ID: <20160622141700.GB2733@red-moon> References: <1465915719-8409-1-git-send-email-sudeep.holla@arm.com> <1465915719-8409-5-git-send-email-sudeep.holla@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1465915719-8409-5-git-send-email-sudeep.holla@arm.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Sudeep, On Tue, Jun 14, 2016 at 03:48:38PM +0100, Sudeep Holla wrote: > This patch adds appropriate callbacks to support ACPI Low Power Idle > (LPI) on ARM64. > > Now that arm_enter_idle_state is exactly same in both generic ARM{32,64} > CPUIdle driver and ARM64 backend for ACPI processor idle driver, we can > unify it and move to cpuidle-arm.h header. > > Cc: Lorenzo Pieralisi > Cc: Mark Rutland > Cc: Daniel Lezcano > Cc: "Rafael J. Wysocki" > Cc: linux-arm-kernel@lists.infradead.org > Signed-off-by: Sudeep Holla > --- > arch/arm64/kernel/cpuidle.c | 17 +++++++++++++ > drivers/cpuidle/cpuidle-arm.c | 23 ++---------------- > drivers/firmware/psci.c | 56 +++++++++++++++++++++++++++++++++++++++++++ > include/linux/cpuidle-arm.h | 30 +++++++++++++++++++++++ > 4 files changed, 105 insertions(+), 21 deletions(-) > create mode 100644 include/linux/cpuidle-arm.h This patch seems fine by me, it would be good if Daniel can have a look too. Some minor comments below. [...] > diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c > index 03e04582791c..c6caa863d156 100644 > --- a/drivers/firmware/psci.c > +++ b/drivers/firmware/psci.c > @@ -13,6 +13,7 @@ > > #define pr_fmt(fmt) "psci: " fmt > > +#include > #include > #include > #include > @@ -310,11 +311,66 @@ static int psci_dt_cpu_init_idle(struct device_node *cpu_node, int cpu) > return ret; > } > > +#ifdef CONFIG_ACPI > +#include > + > +static int __maybe_unused psci_acpi_cpu_init_idle(unsigned int cpu) > +{ > + int i, count; > + u32 *psci_states; > + struct acpi_processor *pr; > + struct acpi_lpi_state *lpi; > + > + pr = per_cpu(processors, cpu); > + if (unlikely(!pr || !pr->flags.has_lpi)) > + return -EINVAL; > + > + /* > + * If the PSCI cpu_suspend function hook has not been initialized > + * idle states must not be enabled, so bail out > + */ > + if (!psci_ops.cpu_suspend) > + return -EOPNOTSUPP; > + > + count = pr->power.count - 1; > + if (count <= 0) > + return -ENODEV; > + > + psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL); > + if (!psci_states) > + return -ENOMEM; > + > + for (i = 0; i < count; i++) { > + u32 state; > + > + lpi = &pr->power.lpi_states[i + 1]; > + state = lpi->address & 0xFFFFFFFF; > + if (!psci_power_state_is_valid(state)) { > + pr_warn("Invalid PSCI power state %#x\n", state); > + kfree(psci_states); > + return -EINVAL; > + } > + psci_states[i] = state; > + } > + /* Idle states parsed correctly, initialize per-cpu pointer */ > + per_cpu(psci_power_state, cpu) = psci_states; > + return 0; Most of the code in this function is FW independent, it would be nice to factor it out and add the respective ACPI/DT helper functions to retrieve idle states count and parameters, we can update it later anyway it is fine by me to leave it as it is. > +} > +#else > +static int __maybe_unused psci_acpi_cpu_init_idle(unsigned int cpu) > +{ > + return -EINVAL; > +} > +#endif > + > int psci_cpu_init_idle(unsigned int cpu) > { > struct device_node *cpu_node; > int ret; > > + if (!acpi_disabled) > + return psci_acpi_cpu_init_idle(cpu); > + > cpu_node = of_get_cpu_node(cpu, NULL); > if (!cpu_node) > return -ENODEV; > diff --git a/include/linux/cpuidle-arm.h b/include/linux/cpuidle-arm.h > new file mode 100644 > index 000000000000..b99bcb3f43dd > --- /dev/null > +++ b/include/linux/cpuidle-arm.h arm-cpuidle.h for consistency with other (ARM) include/linux files ? > @@ -0,0 +1,30 @@ > +#include > + > +#include > + > +/* > + * arm_enter_idle_state - Programs CPU to enter the specified state > + */ > +static int arm_generic_enter_idle_state(int idx) > +{ > + int ret; > + > + if (!idx) { > + cpu_do_idle(); > + return idx; > + } > + > + ret = cpu_pm_enter(); > + if (!ret) { > + /* > + * Pass idle state index to cpu_suspend which in turn will > + * call the CPU ops suspend protocol with idle index as a > + * parameter. > + */ > + ret = arm_cpuidle_suspend(idx); > + > + cpu_pm_exit(); > + } > + > + return ret ? -1 : idx; > +} Either you do this, or we have to add it somehow somewhere in drivers/cpuidle to avoid duplicating it. @Daniel: do you have an opinion on this please ? Thanks, Lorenzo